End-folding machine



April 8, 1952 Filed Aug. 16, 1947 3 Sheets-Sheet l INVENTOR.

April 8,1952

File 'd Aug. 16, 1947,

w. s. CLOUD 2,592,246

1 END-FOLDING MACHINE 5 Sheets-Sheet 2 IN V EN TOR W zifa'azzz 3 CZozzd April 8, 1952 w. s. CLOUD END-FOLDING MACHINE 3 Sheets-Sheet 3 Filed Aug. 16, 1947 a -m a Patented Apr. 8, 1952 END-FOLDING MACHINE William S. Cloud, Wilmette, Ill. Application August 16, 1947, Serial No. 769,047

13 Claims. (01. 270-80) There have' been many folding machines in the past. They have been designed for ordinary folding in which the fold was well spaced from the end of the material being folded. The present folding machine is particularly designed for folding the material quite close to the end thereof.

One of the most economical methods of packaging candy bars and the like is by using bagsets, each comprising perhaps a dozen bags on a common back sheet perforated between the bags for tearing them apart. The bag-sets may be cut from a continuous composite web, including a number of continuous tubes in side-by-side relation on the continuous backing sheet. The short lengths are folded over close to one end of each length to close the tubes to form the bottoms of the bags. It is desirable to have the folded-over end as short as possible so that paper stock will not be wasted. When millions of candy bars are being packaged, minute savings become important. According to the present invention, an exceptionally short fold-over is possible.

An outstanding feature of the present invention is that the tucking blade, which initiates the fold, tucks the fold between two bar-like squeezers, instead of between two squeeze rollers. This permits the bite of the squeezers to be much closer to the folding stop, which positions the folded material prior to its being struck by the blade, than would be possible if the conventional squeeze rollers were used instead of the squeezing bars. It also permits the gripping surfaces to be relatively remote from their operating axes and form a bite with surfaces at a more desirable angle, as compared to former gripping rollers, so that seizing of the folded material in the grippers is more dependable.

Additional objects and advantages of the invention will be apparent from the following description and from the drawings, in which:

Figure 1 is a side view of the end-folding apparatus chosen for illustration of the invention;

Fig. 2 is a fragmentary view of the other side thereof;

Fig. 3 is a fragmentary, perspective view of a bag-set, the end of which has been folded by the apparatus of the invention; and

Figs. 4 to 8 are somewhat diagrammatic views showing the operation of the apparatus in suecessive stages.

Fig. 9 is a fragmentary view showing the crimping teeth formed on the squeezers.

Although the law requires a full and exact de-- scription of at least one form of the invention,

such as that which follows, it is, of course, the purpose of a patent to cover each new inventive concept therein no matter how it may later be disguised by variations in form or additions of further improvements; and the appended claims are intended to accomplish this purpose by particularly pointing outthe parts, improvements, or combinations in which the inventive concepts are found.

General description The general nature of the folder of this invention, and its operation, can best be explained with reference to Figs. 4 to 8. A conveyor ll delivers the bag-set l2 or other piece to be folded to a stop l3. As seen in Fig. 5, a tucking blade M then moves down onto the bag-set l2, partially foldsit and moves it into the bite of the squeezers Hi. The squeezers It in the meantime have moved up to the position shown in Fig. 6 to receive the partially folded bag-set. As seen in Fig. '7, the squeezers l6 carry the bag-set downwardly and as they do so pass through a position in which they are in alignment. In this position, they squeeze the bag-settightly so as to make a sharp fold therein. Shortly after passing this position, the squeezers will move apart and cease to grip the bag-set. At that instant the squeezers are moving at about their maximum speed, and so they throw the bag-sets downwardly. To be sure that a long bag-set moves downwardly fast enough to be out of the way when the squeezers return, a pusher I1 is provided.

Timing of feed Of course, the bags must be fed in timed rlation to the folding apparatus. Any suitable feeder may be used. In the illustrated form, the bag-sets rest on relatively fast-moving belts 2| which are, in turn supported by plates. The I belts move the bag-sets I2 against pins 20 which are carried by chains 23. The chains 23 are driven a little more slowly than the belts 2| so that the bag-sets 12 will be reliably seated against the pins 20. The chains 23 may be supported by rails 24. As the pins pass around sprocket 26, the bag-sets continue under the influence of the belt 2| and slide over a support plate 22 to come to rest against the stop [3 with the forward edge of the bag-set usually resting on ledge 21. g g Y The chain and belts may be driven from the same shaft, not shown, the belts running around a pulley somewhat larger than the pitch diameter of the sprocket.

'51. in Fig. 2.

.near theend of the article being folded.

Drive of folder The folder is driven through shaft 3| which, as seen in Fig. 1, may be driven by a chain 32. The shaft 3! drives crank or crank disk 33 (Fig. 2) which reciprocates link 34 and lever 36. The lever 36 rocks shaft 31, thereby oscillating one of the squeezers 16 of Fig. 4. Intermeshing gear segments 38 of Fig. 1 connect shafts 31 and 39 so that the other squeezer I6 is likewise oscillated. As seen in Fig. 2, shaft 39 bears a crank arm 4| which is connected by link 42 to crank arm 43 on shaft 44. This shaft oscillates arms 46 which carry the tucking blade I4.

The shaft 31 also carries a crank arm 41 which operates a link 48 to oscillate a crank 49, a shaft and the pusher I! carried by the shaft 5| (Fig. 1).

In order that the folder may be driven in synchronism with the feeding belts, the chain 32 may be driven by shaft 53, which in turn is driven by chains 23. The chains 23 may be driven at the far end thereof, not shown, in

any suitable manner. There are two of the chains 23 spaced widely apart so that the pins thereon will maintain the leading edges of As the folded bag-sets are dropped or pushed from the folder, they fall upon a delivery belt 56 which carries them to a suitable stacker. The delivery belt may be driven by a chain or belt The stacker may be actuated by a rod 58 Further description The tucking blade l4 may be, if desired, heated by an electrical heater associated therewith.

.This would be particularly desirable if a heat I tending along the length thereof and held in place by a metal bar 62.

desirable when the bag-sets are of a smooth, glossy, or wax-like finish which makes them difficult to be gripped with suflicient reliability 'by the squeezers to invariably draw them down in the proper manner in spite of the tendency of the tucking blade to lift them.

Even without the rubber gripper the squeezers [B are unusually reliable in seizing the folded article. This results in part from the fact that due to their relatively long radius they can open up sufficiently wide to receive the paper vwhile the angularity of their faces, which must seize the article, is still nearly vertical. The

shafts 31 and 39 are spaced with 4-inch centers,

which means that each squeezer 16 has approximately a 2-inch radius as compared with folders using rollers in place of squeezers I6. This would be comparable to rollers 4 inches in diameter. Such large rollers would not only be expensive, but for many purposes they would be impractical because it would be diflicult to fold anywhere With the squeezers [6 in the form of segmented cylinders (practically all of the cylinder being omitted), it has been found that for most work they need be raised no more than 20 degrees above the horizontal in order to receive the partly folded article. With exceptionally thick articles this might need to be or degrees.

It is especially important that the bag-sets This is particularly 4 for which the present invention is especially intended be gripped reliably because their perforated backing sheets make them relatively fragile. If one end of the bag-set is seized a little before the other end, tearing apart of the bags may result.

The long radius which is permitted by the use of segmented cylinders has another advantage in permitting a sturdy construction. If an attempt were made to fold close to the end of an article by using veiy small rollers, these rollers would be too weak and would need to be reinforced along their length. According to the present invention, the squeezers can make use not only of the strength of the shafts 31 and 39, but also of the plates forming the squeezers l6, and additional reinforcing plates if necessary. The small shafts which might be considered as an alternative would also have to rotate at a high number of revolutions per minute to obtain satisfactory service speed, thereby increasing bearing difliculties.

Another reason the squeezers l6 grip the article reliably is that the gripping surfaces are not initially moving faster than the article. In fact, the squeezers l6 come to a stop as the article is tucked into them and start smoothly. This is the result of the drive by the crank wheel 33 and relationships that bring the squeezers to a stop in the position of Fig. 6. It may be noted, incidentally, that as seen in Fig. 8, the squeezers I6 move downwardly far beyond the distance 'necessary to release the folded article [2. The

result is that at the time of release they are moving with approximately their maximum speed so as to throw the article downwardly at high speed. This, together with the result that there is a substantial interval before the squeezers l8 close again, enables most articles to clear the squeezers before they close. Long articles may be thrown down at a slightly faster speed by the pusher l1.

Another advantage of using squeezers 16 instead of squeeze rolls is that the squeezers may be provided with teeth 66, as seen in Fig. 9, for crimping the fold to make it hold its fold better. If this were done with rolls, the teeth would naturally be in the form of annular ribs which would tend to mar the entire length of the folded article. In practice, the spacing of the teeth on each squeezer I6 is slightly closer than shown and the teeth preferably intermesh slightly.

From the foregoing, it is seen that end-folding apparatus has been developed which, although quite simple, nevertheless reliably folds bags or other articles very close to the ends thereof.

I claim:

1. Folding apparatus including a pair of pivotally mounted squeezers cooperating to form a bite therebetween, means for oscillating the squeezers about their pivotal axes from a receiving position in which they are open, through a squeezing position to a discharge position, said squeezers being so shaped that in the receiving position they leave a gap within the geometric cylinders which would be generated by a complete rotation of the seizing surfaces about said axes, means for delivering an article to be folded to a position close to and across the bite of the squeezers, and means extending into said gap for starting a fold in said article and feeding the fold to the bite.

2. End-folding apparatus, including conveying means for conveying the article to be folded, stop means against which the article is conveyed,

which the squeezers receive the partially folded portion of the article which is pressed between the squeezers by the blade and another angular position at which they eject the folded article; said stop extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment.

3. End-folding apparatus, including conveying means for conveying the article to be folded, stop means against which the article is fed, and having a ledge lying transverse to the direction of feed of the article for supporting the stopped end of the article, a tucking blade parallel to the ledge operable to strike the article resting on said ledge, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers receive the partially folded portion of the article which is pressed between the squeezers by the blade and other angular position at which they eject the folded article; said stop extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment, the gripping surfaces of the squeezers, when positioned to receive the article, being spaced not over degrees from a plane extending through said axes.

4. End folding apparatus, including stop means against which the article is fed, and having a ledge lying transverse to the direction of feed of the article for supporting the stopped end of the article, a tucking blade parallel to the ledge operable to strike the article resting on said ledge, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers receive the partially folded portion of the article which is pressed between the squeezers by the blade and another angular position at which they eject the folded article; said stop extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment.

5. End folding apparatus, including stop means against which the article is fed, and having a ledge lying transverse to the direction of feed of the article for supporting the stopped end of the article, a tucking blade parallel to the ledge operable to strike the article resting on said ledge, squeezers comprising a pair of coperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers receive the partially folded portion of the article which is pressed between the-squeezers by the blade and another angular position at which they eject the folded article; said stop extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment, the gripping surfaces of the squeezers being formed with staggered teeth to crimp the fold.

6. End folding apparatus, including stop means against which the article is fed, and having a ledge lying transverse to the direction of feed of the article for supporting the stopped end of the article, a tucking blade parallel to the ledge operable to strike the article resting on said ledge, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers receive the partially folded portion of the article which is pressed between the squeezers by the blade and another angular position at which they eject the folded article, said stop extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment, at least one of the squeezers carrying a member formed of resilient material of high frictional characteristics projecting toward the other and positioned to grip the article.

7. End-folding apparatus, including preliminary means for partially folding an article and advancing it, squeezerscomprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers receive the partially folded portion of the article and another "angular position at which they eject the folded article; said preliminary means including an article positioning member extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment, the gripping surfaces of the squeezers, when positioned to receive the article, being spaced not over 20 degrees from a plane extending through said axes.-

8. End-foldin apparatus, including preliminary means for partially folding an article and advancing it, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers receive the partially folded portion of the article and another angular position at which they eject the folded article; said preliminary means including an article positioning member extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment.

9. End-folding apparatus, including preliminary means for partially folding an article and advancing it, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers receive the partially folded portion of the article and another angular position at which they eject the folded article; said preliminary means including an article positioning member extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment, said means for oscillating imparting approximately a maximum forward speed to the squeezers at the position of release of the folded article to eject it quickly from the folder.

10. End-folding apparatus, including preliminary means for partially folding an article and advancing it, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, means for oscillating the squeezers between one angular position at which the squeezers receive the partially folded portion of the article and another angular position at which they eject the folded article and separate to permit its further movement be- -tween them, and means for pushing the article after it is released to increase its speed; said preliminary means including an article positioning member extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment.

11. End-folding apparatus, including stop means against which the article is fed, and having a ledge lying transverse to the direction of feed of the article for supporting the stopped end of the article, a tucking blade parallel to the ledge operable to strike the article resting on said ledge, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers are approximately stationary and receive the partially folded portion of the article which is pressed between the squeezers by the blade and another angular position at which they eject the folded article; said stop extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment.

12. End-folding apparatus, including stop means against which the article is fed, and having a ledge lying transverse to the direction of feed of the article for supporting the stopped end of the article, a tucking blade parallel to the ledge operable to strike the article resting on said ledge, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers are approximately stationary and receive the partially folded portion of the article which is pressed between the squeezers by the blade and another angular position at which they eject the folded article; said stop extending closer to the pivotal axis of one of the cylinder segments than the radius of that segment, said means for oscillating imparting approximately a maximum forward speed to the squeezers at the position of release of the folded article to eject it quickly from the folder.

13. End-folding apparatus, including stop means against which the article is fed, and having a ledge lying transverse to the direction of feed of the article for supporting the stopped end of the article, a tucking blade parallel to the ledge operable to strike the article resting on said ledge, squeezers comprising a pair of cooperating segmented cylinders mounted to move about axes parallel to said ledge, and means for oscillating the squeezers between one angular position at which the squeezers are approximately stationary and receive the partially folded portion of the article which is pressed between the squeezers by the blade and another angular position at which they eject the folded article, said means for oscillating imparting approximately a maximum forward speed to the squeezers at the position of release of the folded article'to eject it quickly from the folder.

WILLIAM S. CLOUD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 429,262 Cundall June 3, 1890 465,119 Tucker Dec. 15, 1891 1,541,351 Hall June 9, 1925 2,205,005 Anderson June 18, 1940 2,339,304 Von Haase Jan. 18, 1944 2,376,360 Irmscher May 22, 1945 FOREIGN PATENTS Number Country Date 469,937 Great Britain Aug. 3, 1937 

